云南北衙表生金矿形成与保存探讨  

Formation and Conservation of Beiya Epigenetic Deposit, Yunnan Province

作　　者：肖骑彬[1] 蔡新平[1] 徐兴旺[1] 

机构地区：[1]中国科学院地质与地球物理研究所,北京100029

出　　处：《矿床地质》2003年第4期401-407,共7页Mineral Deposits

基　　金：云南省省院省校合作项目 (编号 :YK980 0 8)的部分成果 ;国家自然科学基金项目 (编号 :40 2 72 0 90 )的资助

摘　　要：通过对云南北衙地区表生金矿形成的地质背景、矿床特征等的研究 ,重点探讨了其特殊的形成与保存条件。认为北衙地区的表生金矿是“古砂矿” ,它的巨大蕴藏量主要得益于其特殊的形成与保存条件 :丰富的原生金矿为其提供充足的成矿物质 ,特别发育的古喀斯特洞穴为“古砂矿”提供了特殊的储存空间 。In Beiya district, the epigenetic gold deposits are actually 'paleoplacer' deposits. Their formation has no essential difference from that of modern placer deposits in South China. The preservation of large quantities of gold resources is attributed to the special conservation conditions in Beiya. Various karst caves provided the necessary sites for epigenetic mineralization, while the breccias produced by gas_liquid explosion provided the excellent conservation environment. In this paper, the epigenetic gold deposits are divided into three main types, i.e., paleoplacer deposits of river_lake phase, paleoplacer deposits of surface_covered karst fracture_caves, and paleoplacer deposits of paleo_weathering crust. The genesis of each kind of paleoplacer deposits is investigated, and the conservation of the paleoplacer deposits is emphatically discussed.

关 键 词：云南 表生金矿 地质背景 矿床特征 气液爆破作用 热水角砾盖层 

分 类 号：P618.51[天文地球—矿床学]